Along with the development of technology, wide-angle camera lenses, including ultra wide angle lenses, fish-eye lenses and other camera lenses whose visual angles are greater than standard lenses, are becoming important in increasingly more occasions, such as photography, security protection, measuring, projecting, recreation and vehicle-mounted devices. In the field of photography, because the characteristics of short focal lengths and large fields of view of wide-angle camera lenses, the acquired unique barrel distortions will bring the observers strong visual impact. As another example, in the field of measuring, because wide-angle camera lenses have the characteristic of large fields of view, and imaging for once can obtain more amount of information, the data that can be obtained by measuring are increased. As another example, in the field of projecting, commonly used projector lenses are to image in a plane, but fish-eye lenses of large fields of view can image in a round sky screen, which in the watching brings the observer an immersed watching feeling of watching the starry sky in a summer night. As another example, in the field of vehicle-mounted applications, with the ultra-large field angles, the side area that can be observed is broader, which will effectively facilitates the applications of car reversing and all round looking. The photosensitive elements of general optical systems are merely Charge Coupled Device (CCD) or Complementary Metal-Oxide-Semiconductor Transistors (CMOS). Along with the progress of the semiconductor manufacturing process technique, the pixel sizes of photosensitive elements are decreasing, and optical systems tend to have more pixels and higher imaging quality. Additionally, in consideration of the popularization of the products, camera lenses are required to have increasingly smaller sizes, and increasingly lower cost is required.
Presently, general wide-angle camera lenses mostly employ all-glass constructions. For example, as shown by the patent with the patent number of “WO201603732A1”, a camera lens consists of seven glass optical lenses, to provide a photographic object lens with a large relative aperture and a small volume. However, the ceaseless development of portable electronic products proposes higher requirements on the miniaturization, the light weight trend, the wide angle trend and the imaging quality of camera lenses. In order to satisfy the requirements on miniaturization and light weight trend, it is required to further shorten the overall lengths of the camera lenses and employ plastic optical lenses. However, the conventional all-glass structures cannot further shorten the overall system length and enlarge field angles while ensuring the imaging quality. The emerging of precision finishing enables the industrialized production of the processing of aspheric surfaces. Precision finishing technique does not only comprise the direct grinding aspheric surface processing of glass materials, but also comprise the die casting aspheric surface processing of glass materials and the jet molding aspheric surface processing of plastic materials. Generally, the employing of aspheric surfaces cannot only remarkably improve the image quality and decrease the aberration, but also reduce the number of the optical lenses of the camera lenses and reduce the volumes. The materials of aspheric optical lenses include glass and plastic, and the aspheric optical lenses of glass materials can be processed by abrasive machining and die casting. The employing of aspheric surfaces tremendously facilitates the performance buildup of wide-angle camera lenses.